What causes either pump or dump of any asset? It's basically just liquidity. Bitcoin's overall trend suggests that it will still pump but pinpointing what price mark it will get to exactly isn't that easy. Buying pressure is basically what constitutes the pump of price of an asset and similarly selling off by some investors after reaching a particular pump price is what causes retracement. If the overall buy pressure isn't strong enough then that retracement may very well escalate to a downtrend.
What's the point of all this? Black rock is a big firm and as a result they have enough liquidity to kick off a strong pump before the news of it causes FOMO that also improves the pump. This is basically why most of their speculations turn out true.
anyone studying bitcoin economics can plainly see the price wants to go up naturally but is currently being held down via whale suppression (market order walls)
there are many, many countries whereby mining bitcoin can cost them upto $350k/btc so naturally buying bitcoin on the market at the moment is good discount to them.
the institutional whales however from other countries dont want the price to jump so quick just yet as they want to be buying more coin while prices are low.
knowing that if the entire planet can mine for less than say $400k, then no one is silly to pay on the market for more then other ways to acquire bitcoin
(the same economic mentality was proven in 2021 when the market tested the $70k top which had a planetary max mining cost of $75k at the time)
however yes although economic logic shows that getting to $700k soon is impractical economically, we also dont know if the whales will let the market test the economically logically upper limit of under $400k, the whales may keep the price suppressed to any number under $350k
..
as for blackrock itself. their revenue is not that high(only $1b-$6b). and they cant just liquidate their sponsors coin that are locked up in trust.. it is however the sponsors who could liquidate shares to then liquidate btc out of the locks and then use that fiat to play the markets(or use other fiat they may have access to)
in short "blackrock" is not the whale, its blackrocks sponsors that bought coin deposited it with blackrock in trust, and then got the baskets of shares for the sponsors to sell shares on blackrocks platform to the sponsors customers, whom are the whales related to blackrock (the sponsors and sponsors customers)